Flew external links made by different users at the same time, what could be?

Question

ownCloud/Nextcloud

Colleagues, good afternoon!

There is a problem, the users of our cloud make external links for other departments for collaboration, but at one moment absolutely all the external links that were made earlier fly off.
This is clearly not the expiration date of the link, but something else, because users make links at different times, but they all crash at the same time.
I didn’t dig much in the admin panel, is it possible to set up updating external links there, let’s say once every 1-2 weeks?